title: Ribosomal RNA (rrn) operons in Streptococcus mutans and nucleotide sequence of tRNA(Pro) gene associated with rrnB.
abstract: Using a cloned 0.5-kb probe containing an internal fragment of 23S ribosomal RNA from the rrnB operon of Streptococcus mutans, we analyzed various endonuclease digests of the chromosomal DNA isolated from human-derived strains of mutans streptococci. Thus far, the examined S. mutans strains exhibited five ribosomal operons. Here, we describe a ribotyping technique for S. mutans based on restriction and Southern blot analyses with the biotin-labeled homologous probe and chemiluminescence detection. We cloned and sequenced a unique gene encoding tRNA(Pro) downstream from 23S rRNA gene at the 3' end of the operon. Primers designed to the 3' end of the rrnB operon PCR-amplified a 2.3-kb DNA fragment in all tested strains. Restriction fragment length polymorphism analysis of the amplicon revealed a diversity of the single locus among S. mutans isolates, thus establishing a potential use of the technique for the molecular epidemiology of mutans streptococci.
authors.affiliation: University of Alabama at Birmingham, School of Dentistry 35294, USA.
authors.forename: J
authors.initials: J
authors.lastname: Novák
authors.forename: G R
authors.initials: GR
authors.lastname: Shah
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: P W
authors.initials: PW
authors.lastname: Caufield
mesh_terms: D001483:Base Sequence; D015342:DNA Probes; D004269:DNA, Bacterial / Q000032:analysis; D005798:Genes, Bacterial; D018740:Genetic Heterogeneity; D008969:Molecular Sequence Data; D012150:Polymorphism, Restriction Fragment Length; D012361:RNA, Transfer, Pro / Q000235:genetics*; D015183:Restriction Mapping; D013295:Streptococcus mutans / Q000145:classification / Q000235:genetics*; D012407:rRNA Operon
chemical_list: D015342:DNA Probes; D004269:DNA, Bacterial; D012361:RNA, Transfer, Pro